Hospital costs associated with atrial fibrillation for patients with ischemic stroke aged 18-64 years in the United States.

Background And Purpose: Hospital costs associated with atrial fibrillation (AFib) among patients with stroke have not been well-studied, especially among people aged <65 years. We estimated the AFib-associated hospital costs in US patients aged 18 to 64 years.

Methods: We identified hospital admissions with a primary diagnosis of ischemic stroke from the 2010 to 2012 MarketScan Commercial Claims and Encounters inpatient data sets, excluding those with capitated health insurance plans, aged <18 or >64 years, missing geographic region, hospital costs below the 1st or above 99th percentile, and having carotid intervention (n=40 082). We searched the data for AFib and analyzed the costs for nonrepeat and repeat stroke admissions separately. We estimated the AFib-associated costs using multivariate regression models controlling for age, sex, geographic region, and Charlson comorbidity index.

Results: Of the 33 500 nonrepeat stroke admissions, 2407 (7.2%) had AFib. Admissions with AFib cost $4991 more than those without AFib ($23 770 versus $18 779). For the 6582 repeat stroke admissions, 397 (6.0%) had AFib. The costs were $3260 more for those with AFib than those without ($24 119 versus $20 929). After controlling for potential confounders, AFib-associated costs for nonrepeat stroke admissions were $4905, representing 20.6% of the total costs for the admissions. Both the hospital costs and the AFib-associated costs were associated with age, but not with sex. AFib-associated costs for repeat stroke admissions were not significantly higher than for non-AFib patients, except for those aged 55 to 64 years ($3537).

Conclusions: AFib increased the hospital cost of ischemic stroke substantially. Further investigation on AFib-associated costs for repeat stroke admissions is needed.